Glutamax

[Chutney]

In article <1994Sep13.104929.27021 at aber.ac.uk>, crb at aber.ac.uk wrote:

>         Most cell biologists know the problems regarding L-Glutamine,
and its instability 
>         particularily at temperatures required for mammalian cell culture.
>         Can anyone advise me of the merits of 'Glutamax'.
>         Is it a realistic alternative, is cell growth or viability
compromised ?
>         I would be grateful of any advice on this subject.
>  
We have never actually encountered any problems with glutamine.
Assuming that it is kept frozen until it is incorporated into medium and 
then is kept at +4°C you should have no troubles.  We work here on the bacterium
Chlamydia trachomatis which shows a great change in morphology and growth
pattern with AA limitation and this 'indicator' has never suggested that
we have a medium problem.
One thing that most people do not do which they should is to 'snap freeze'
all amino acids in liquid nitrogen and then transfer tham to -20°C
for long term storage.  This rapid freezing ensures that the amino acid 
solution freezes as a homogeneous solution.  Freezing slowly at -20°C
allows partitioning of the water and solution and reduces the shelf life
of the AA.
I hope that this may be of use to you.